Wettest Summer on Record in Berlin

Berliner Wetterkarte at Freie Universität: Record Set after Only Two Months

№ 208/2017 from Jul 31, 2017

According to calculations by the Berliner Wetterkarte association at Freie Universität Berlin, the summer of 2017 in the region around the German capital has already gone on record as the wettest summer since the beginning of the weather records in Berlin-Dahlem. Even a long dry period in August wouldn't change that, said meteorologist Petra Gebauer on Monday. Since 1908, when the record keeping began, no summer has had this much precipitation. In June and July the low pressure zones RASMUND, ZLATAN, and ALFRED brought 373.5 liters of rain per square meter to Berlin-Dahlem. This was more precipitation than was measured for the entire summer of 2007, which has so far been considered the wettest summer on record. "This new record was reached even though there was only a significant amount of rain on slightly more than half of the past 60 days," stressed Petra Gebauer. There were, however, two short intensive periods of one shower after another and one continuous rainy period.

At the end of June there was a 24-hour period in Dahlem when 93 liters of rain fell per square meter – the third highest daily value in 110 years in June. In norther Berlin more than 200 liters of rain per square meter were measured. On July 22 unusually violent thunder storms brought 42 liters per square meter in only one hour to Tegel Airport. The low pressure zone ALFRED was also responsible for the heavy rain at the end of July in the region of the Harz Mountains, according to Gebauer. Recent data from the German Weather Service showed that 302 liters of precipitation were measured within 72 hours at the Ecker Dam in the Harz region.

Can the region around Berlin expect a return to drier weather? "Not yet," said Gebauer. "When precipitation during the first week in July is high like it was this year, 65 per cent of the time it last seven weeks." The current weather situation with a series of low-pressure areas is not over yet. "According to the folk saying ‘Wie die sieben Brüder das Wetter gestalten, so soll es noch sieben Wochen lang halten’ (With seven brothers shaping the weather, it will stay the same for seven weeks.). The weather changed at the end of June and beginning of July, so rain and sun are likely to alternate until the middle of August, when a more stable high-pressure zone should set in."

The meteorologists at Freie Universität Berlin continue to sell naming rights for European high and low pressure zones. The proceeds are used to finance the Dahlem Weather Station, where meteorology students observe the weather around the clock. Their series of weather observations has been going on for more than 100 years and is one of the longest continuous records in existence. In 2017 the high pressure zones are being given female names, and lows male names.